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New chapter from myself in a Springer volume: “Access to Health Care in Sub-Saharan Africa: Challenges in a Changing Health Landscape in a Context of Development”

SpringerBook_I wrote a chapter for “Health in Ecological Perspectives in the Anthropocene” edited by Watanabe Toru and Watanabe Chiho. I have no idea if they are related. Either way, my chapter “Access to Health Care in Sub-Saharan Africa: Challenges in a Changing Health Landscape in a Context of Development” occupies pages 95-106 in the volume.

Check it out, you can buy the book through Amazon for a cool $109, or just my chapter through the Springer site for $29 or you can simply write me and I’ll give you a synopsis.

Success!

Here’s the abstract for the book:

This book focuses on the emerging health issues due to climate change, particularly emphasizing the situation in developing countries. Thanks to recent development in the areas of remote sensing, GIS technology, and downscale modeling of climate, it has now become possible to depict and predict the relationship between environmental factors and health-related event data with a meaningful spatial and temporal scale. The chapters address new aspects of environment-health relationship relevant to this smaller scale analyses, including how considering people’s mobility changes the exposure profile to certain environmental factors, how considering behavioral characteristics is important in predicting diarrhea risks after urban flood, and how small-scale land use patterns will affect the risk of infection by certain parasites, and subtle topography of the land profile. Through the combination of reviews and case studies, the reader would be able to learn how the issues of health and climate/social changes can be addressed using available technology and datasets.

The post-2015 UN agenda has just put forward, and tremendous efforts have been started to develop and establish appropriate indicators to achieve the SDG goals. This book will also serve as a useful guide for creating such an indicator associated with health and planning, in line with the Ecohealth concept, the major tone of this book.  With the increasing and pressing needs for adaptation to climate change, as well as societal change, this would be a very timely publication in this trans-disciplinary field.

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Infectious disease transmission dynamics and the ethics of intervention based public health research

I think a lot about ethics and ethical issues. Research in Sub-Saharan Africa presents unique risks for ethical breaches. Given income and power disparities between individuals and foreign researchers and even between individuals and local political leaders the possibility of coercive research is ever present. Pressure to produce can lead to unrealistic assumptions of risks and benefits to very poor individuals. Inadequate knowledge or willful ignorance of local political issues can compromise future research activities, both by international and domestic groups.

Recently, though, an interesting situation came across my desk that included an intersection of ethics and the dynamics of infectious disease transmission.

As everyone knows, not all infectious diseases are the same. Some, like measles, impart full immunity upon exposure, whereas diseases such as malaria impart only partial immunity, requiring repeated exposures to acquire full or adequate immunity to prevent death or serious injury. Moreover, as immunity and immune reactions change over the life course, the time (age) of exposure are sometimes crucial to prevent serious disease. Polio is a great example. Exposure in infancy leads merely to diarrhea, where exposure at older ages can lead to debilitating paralysis.

I was thinking of an population based intervention study which provides some sort of malaria medication to a small population in a holo-endemic area. Given the year round nature of malaria transmission in this area, we would expect that even with a depression in symptomatic and asymptomatic cases, active transmission in the surrounding areas would lead to recrudescence within a very short time. Given the short time frame, we would assume very little interruption in the development of immunity in small children and might even see a short term reduction of childhood mortality. Assuming that this medication presented little or no risk of serious side effects, I believe that there is little reason to assume an ethical breach. A short term reduction in malaria would suggest that the benefits far outweigh the risks.

However, conducting the same study on a very large population in the same area might have very different outcomes. Delivering a malaria medication to, say, an entire county surrounded by other areas of extremely high transmission would indicate that recrudescence is also inevitable but that the time required to return to pre-intervention levels is extended. Infectious disease transmission requires a chain of hosts. The longer that chain, the longer it will take for new hosts to become newly infected.

Theoretically, this could delay infections in small children and it is theoretically possible that we might see a spike in childhood mortality, since the timing of initial malaria infection and frequency of infections are crucial to preventing the worst outcomes.

Of course, I’m not suggesting that people should just get infected to induce immunity, but I am suggesting that a study which seeks to reduce transmission through pharmaceuticals given only intermittently (as opposed to prophylactically) consider all possible implications. Insecticide treated nets (ITNs) provide protection over time and are a form of vector control. A medication given at a single time point merely clears the parasite, but does nothing to prevent bites or kill mosquitoes.

Though I could be overthinking the issue, my worry is that ethical approvals approach the issue of mass distributions of pharmaceuticals as a one size fits all issue without taking other factors such as population size and acquired immunity into account. Malaria, as a complex vector borne disease introduces complexities that, say, measles does not. Researchers, IRBs and ethics board would do well to consider this complexity.

New Publication (from me): “Insecticide-treated net use before and after mass distribution in a fishing community along Lake Victoria, Kenya: successes and unavoidable pitfalls”

mjThis was was years in the making but it is finally out in Malaria Journal and ready for the world’s perusal. Done.

Insecticide-treated net use before and after mass distribution in a fishing community along Lake Victoria, Kenya: successes and unavoidable pitfalls
Peter S Larson, Noboru Minakawa, Gabriel O Dida, Sammy M Njenga, Edward L Ionides and Mark L Wilson

Background
Insecticide-treated nets (ITNs) have proven instrumental in the successful reduction of malaria incidence in holoendemic regions during the past decade. As distribution of ITNs throughout sub-Saharan Africa (SSA) is being scaled up, maintaining maximal levels of coverage will be necessary to sustain current gains. The effectiveness of mass distribution of ITNs, requires careful analysis of successes and failures if impacts are to be sustained over the long term.

Methods
Mass distribution of ITNs to a rural Kenyan community along Lake Victoria was performed in early 2011. Surveyors collected data on ITN use both before and one year following this distribution. At both times, household representatives were asked to provide a complete accounting of ITNs within the dwelling, the location of each net, and the ages and genders of each person who slept under that net the previous night. Other data on household material possessions, education levels and occupations were recorded. Information on malaria preventative factors such as ceiling nets and indoor residual spraying was noted. Basic information on malaria knowledge and health-seeking behaviours was also collected. Patterns of ITN use before and one year following net distribution were compared using spatial and multi-variable statistical methods. Associations of ITN use with various individual, household, demographic and malaria related factors were tested using logistic regression.

Results
After infancy (<1 year), ITN use sharply declined until the late teenage years then began to rise again, plateauing at 30 years of age. Males were less likely to use ITNs than females. Prior to distribution, socio-economic factors such as parental education and occupation were associated with ITN use. Following distribution, ITN use was similar across social groups. Household factors such as availability of nets and sleeping arrangements still reduced consistent net use, however.

Conclusions
Comprehensive, direct-to-household, mass distribution of ITNs was effective in rapidly scaling up coverage, with use being maintained at a high level at least one year following the intervention. Free distribution of ITNs through direct-to-household distribution method can eliminate important constraints in determining consistent ITN use, thus enhancing the sustainability of effective intervention campaigns.

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